Continuous sound recording and reproducing system



Nov. 14, 1944; H. P. CLAUSEN v CONTINUOUS SOUND RECORDING AND REPBODUCING SYSTEM Filed Sept. 25, 1942 n W a C P m m H Patented Nov. 14, 1944 um'rso STATES PATENT orries CONTINUOUS SOUND RECORDING AND REPRODUCIN G SYSTEM Henry P. Clansen, White Plains, N. Y., assignor to The Gray Manufacturing Company, Hartford, Conn, a corporation of Connecticut Application September 25,1942, Serial No. 459.661

'2 Claims. (01. ii-100.4)

. the next machine of the group and so on through the entire series, and if necessary back to the first machine of the group for repetition of the cycle as required.

An object of this invention is to provide automatically operating apparatusin a system of this type, wherein during recording a. predetermined amount of terminal recording of one machine is simultaneously recorded as the initial amount on the next machine of the series, so that the recording may in effect he said to overlap.

A further object of this invention is the provision in such a system of an arrangement wherein each machine in use initiates the operation or the next machine of. the series near the end of therecording on the machine'in use.

, A still further object of this invention is to provide in such a system means acting during reproduction to cause the immediate shut down of the machine in use when the next machine of v the series starts up, so as not to cause distortion in the sound reproduction.

An important object of this invention is to provide in such a system means at the dictator station whereby starting and stopping of any of the machines may be efl'ected by the dictator, and wherein this starting and stopping control is automatically shifted through the cycle, so that the particular machine in use can be started and stopped as required. I

A still further object of the invention is to provide manually operated means whereby an attendant for the machines may at any time shift the recording or reproduction from the machine number of machines may be included in the sysa in use to the next machine of the series without 1 is a schematic and diagrammatic illustration of the subject matter of this invention as applied to three sound recording and. reproducing machines. Similar reference numerals have been used throughout to indicate the same or similar parts. I

Those who are acquainted with the subject matter of this art will understand from. this disclosure that the subject matter of this invention may be applied to many different forms and types of sound recording and reproducing machines. For purposes of illustration. however, the inven tion has been shown as applied to a sound recording machine which is of the type disclosed in the copending application of Proctor and V'Ihiede, Serial No. 218,082, filed July 8, 1938, now United States Patent No. 2,296,870, issued September 29, 1942.

In a machine of this type the record tablet which is a thin disc of cellulose acetate or the like, is mounted upon the rotatable spindle of a carriage which is adapted to have rectilinear movement along guides in a direction radial of the record tablet. The sound recording and reproducing heads which may be alternatively applied to the record tablet are relatively fixed and the driving power for the device to cause movement of'the carriage is applied to the recordtablet itself by gripping it between a pair of .Iriction rollers, one of which is power driven and the other of which is an idler. The rotation of the tablet causes rotation of the spindle upon which it is keyed, which in turn through suitable mechanism as disclosed in the above patent causes the movement-o1 the carriage. Of course, it is apparent that it is immaterial whether the support for the record tablet moves or the sound recording and reproducing heads move, so long as relative movement therebetween is effected.

the form of a fine pitch spiral recording outwardly until the periphery thereof is reached.

Referring now to the drawing it is first to be noted that there is illustrated therein the mechanism necessary for the employment of this invention in a system comprising three separate sound recording and reproducing machines. Respective portions of these machines are separated by broken dash lines. as shown, and, of course, the

. connections between themachines may be permanent or may be temporarylby means of cables and suitable connectors as previously mentioned. Since the mechanism for each machine is a duplicate of every other machine, only a description of one machine will be given in detail. As illustrated diagrammatically, the carriage is shown at l, and it may be assumed that in its motion will move back and forth between left and right in the plane'of the paper. tratedat 2 and is diagrammatically shown as self supporting, although, as previously mentioned, it may be. of the thin fiexible type. It is keyed to the vertical spindle journaled on the carriage, and is rotated by means of a power driven wheel, not shown, which will engage the record on its under surface below the point of contact between the record and the idler roller 3. The axes of these rollers will be in the plane of the paper, as is apparent from the above mentioned patent, but

for the sake of simplicity not illustrated and shown. The friction idler roller 3 is rotatably mounted on the end of a pivotally mounted lever which is grounded as shown. The power driven roller engages the under surface of the record tablet at all times, and will not drive unless the record isclamped between it and the idler roller lby moving the idler roller 3 down into engagement with the upper surface of the record tablet.

included as part of the machine and connected in any suitable manner with the lever provided to shift from recording to reproduction, is a switch 4 which includes a movable member having three switch blades mounted thereon, as indicated by small circles in the drawing. This switch is'shown in neutral position, at which time neither the recorder nor the reproducer engages the record tablet. connected to the input and output of a suitable amplifier 1 which is preferably a multi-stage vacuum tube amplifier of the proper characteristics. Single wire circuits are illustrated for the sake of simplicity. It is to be noted, however, that The record tablet is illusv Two of the movable contacts are the lower contact of this pair of contacts is ,con-

nected to the input of the amplifier, and the upper contact-is'connected to the output. These two movable contacts cooperate with a pair of fixed contacts as shown, provided with acommon connection 40 to the fixed contact of a switch IS. The third movable contactof the switch 4 is grounded as shown, and cooperates with the fixed contact which is connected by wire 28 to the fixed contact of switch 21. The upper contact of the amplifier pair cooperates with a fixedcontact connected to the grounded recording head 5, which may be of any form suitable for this purpose. The other fixed contact cooperating with the. amplifier pair is connected by wire to the ground-' ed sound reproducing head 6,'-likewise of any. form suitable for the purpose.

While, the subject matter of this invention is not particularly concemedwith such details, the switch 4 may be mechanically or electrically aswill be properly positioned depending upon the recording or reproducing function.

At the dictators station, which may be at the machines, or remote with respect thereto, is a combined microphone-loud speaker unit 8 which has one terminal grounded and its other terminal connected by wire as shown to the movable contact of switch l6. It is mentioned, although apparent from the drawing, that this connection similarlyconnects to each of the switches it of the other machines in the system, as for example switches l6 and 16''. At the dictators station is a start-stop switch In, one contact of which is grounded and the other contact of which is connected by wire I I to the movable contact of switch l2. This movable contact cooperates with a front and a back contact and the former is connected by wire H t the movable contact of switch I2 of the second machine, and so on through the series. Switches li'and ii are part of a relay having the energizing winding l3 and including a a latch I4 which cooperates with a catch I5 so that when the winding I3 is energized the switches shift to their other position and are locked in that'position by engagement between latch I4 and catch l5.

At this point it will be noted that the system as illustrated isshown as a grounded system for simplicity, All the live or positive terminals of the various devices are indicated by the letter S and it will be'understood that the power system, not shown, will be grounded at one terminal and its other terminal will be connected to all of the terminals of the system marked S.

The backcontact of switch I2 is connected by wire H to movable contact of switch i8 which includes a front and back contact. The former is connected by wire 19 to one terminal of a ma netic actuating device 29 for raising and lowering the lever which supports the idler roller 3. There are many suitable forms of magnetic actuators so that this element has only been diagrammatically illustrated. Any type of device which will move the lever down upon one energization, where it will remain until the next energization, whereupon it will be raised, is suitable for the purpose. This arm or lever cooperates with a pair of fixed contacts so as to engage them when the lever is in its down position. One of these contacts is connected by wire 2| to a contact finger 22 mounted upon but insulated from the carriage I, so as to travel with it. The contact finger 22 cooperates with a fixed contact finger 23 which is positioned so that these fingers engage when the recording or reproduction comes within a predetermined distance from the end of the record. Contact finger 23 is connected to the operating winding 24 of a relay which includes the switches I8, 21, 48,30 and 3|.

The other fixed contact controlled by the lever of idler roller 3 is connected by wire 25 to one terminal of the operating winding 26 of a relay which includes a switch 41. Switch 4'! is in a cirsociated with the mechanism for shifting the recorder and reproducer into use, so that the switbh cuit including a signal lamp 9. at the dlctators station, which may be of any suitable type, but

21 and by branch connections to the fixed contact of a switch 60 to the unlatching winding 80 of the relay I3. The other contact of switch 60 is grounded as shown. The second contact of the pair of switch 29 isconnected by wire I9, and

the movable contact of this switch is grounded as shown.

The fixed contact of switch 30 is grounded and its movable contact is connected by a wire to one terminal of a solenoid 31 whose plunger is connected to a dash-pot 32 biased so that the plunger will ascend slowly upon the energization of theconnection S. The result of this is the momensolenoid 31 to return quickly upon its de-ener-' gization. This plunger is positioned so that at the end of its upward stroke it will engage switch 29. I v

The movable contact of switch 48 is grounded and its fixed contact is connected by wire I9 .to the magnetic startingdevicezll for the second machine and by branch connections to the back contact of switch I 8', one vof the fixed contacts of switch 29 and the fixed contact of switch 34.

At this point it may be noted that the fixed contact of switch 34 is connected to wire I9. The

movable contact of switch 3| is grounded and the fixed contact connected by wire 42 to the winding I3 of the relay of the second machine and by a branch connection to one of the movable contacts of switch 34'. At this point it will be noted that one of the movable contacts of switch 34 is also connected to the winding I3. The movable contacts of switch 3.4 and its equivalent switches in the other machines is grounded, as shown.

The front contact of switch I2 is connected as shown to the back. contact of switch I8.

-While it. is of no importance to an under.- standing of this invention, it will be understood that most of the control equipment for each machine may be embodied in a single compact unit which may be provided with receptacles for cable and plug connection for facilitating in connecting in to the recording and reproducing machine with which it is to be associated, with the control unit of the next machine and with .power circults. Likewise, each machine may be readily provided with connectors for the relay 26, signal light 9, transmitter-reproducer 8 and start-stop switch III. Likewise, it is apparent that these control units may be completely uniform and each may be provided with a signal light, arelay skilled in. the art and-do not affect the nature of the scope of the invention.

A description of the operation of this systemwill now be undertaken. It will be assumed that the particular installation to be described includes, as shown, .three sound recording and reproducing machines and three control units con- .nected up as shown. It will further be assumed that the machinesihave all been prepared for recording either by the, dictator or an attendant,-

so that each machine is providedwith a fresh record tablet and each machine is conditioned so as to start recording at the beginning of the rec 0rd. It will be assumed that the power disc roller, ,not shown. is in operation or the-control for its for the signal light, and a start-stop switch. These minor variations will be apparent to those tary energization of the winding I3, causing switch I2 to shift to its back contact, switch I6 to close, and latch I4 to be engaged by the catch I5, so that switches I2 and I6 remain in actuated position. The circuit from wire II then passes through the back contact of switch I2, wire I'I,

front contact of switch I8, .wire I9 to the startstop winding 20. If switch I0 is held closed for several seconds, the circuit will then shift to the winding 20, pulling the lever for idler friction roller 3 down into driving position. If the closing of switch III was only momentary, it will then require a second closing to actually start the first machine. No other circuits. from wire I9 are completed at this time.

The downward movement of the lever supporting the roller 3 completes a circuit from ground through wire 25, through relay 26, closing switch 1 and energizing the signal light 9 showing the dictator that a machine is readyfo'r recording. The dictator need then only speak into the microphone 8, the circuit for which is completed from ground through the microphone to switch I6, and thence by wire, 46 to the input contact of switch 4 for amplifier I, through the amplifier to the output circuit, through the output contact, and thence to the recording head 5 and to ground, as will be apparent. As the dictation continues, carriage I moves slowly to the left. At any time the dicator may stop the machine by again momentarily closing ,switch- III, which .again completes a circuit through the back conthe lever from roller 3, wire 2|, fingers 22 and 23 v to the relay' winding 24. A number of new cirof switch I8 and wire I9,to start-stop the windand the-lowermost movable contact is out of en- 75 cults are now established. Instantly the control by switch Iflthrough wire I! shifts through the working contact of switch I8 to wire II and by itto the movable contact of switch-I2. At the same time the closing of switch 3i completes a circuit from ground through that switch and by wire 42 to relay winding I3. The energizat on of the relay [3' immediately closes switch I6 and shifts the movable contact of switch I 2' to its back contact. These switches are latched up in this position by the engagement ofcatch I5 with latch I4. The shifting of the control switch Ill to switch I2 makes it immediately possible to start and stop the second machine from the dictators station through wire I'I',- the front contact ing 20f of the'second' machine. However. th s machine'has already been started by the clos n of switch. to set up a circuit from ground 4 through wire I9 so that at the instant of energization of relay'24 the lever for roller I3 descending and the second machine starting to record. It will, of course, be apparent that switch It will likewise 4 will have previously been moved down to recording position since we assume that all of the machines were set for recording when required.

Also, at the instant of energization of relay 24, switch 30 was closed, completing a circuit from ground to the solenoid under the bias of the dash-pot 32 began to rise slowly. After a few seconds, as determined by operating conditions, this plunger will close switch 29, which will accomplish several operations. The first of these is to complete a circuit to the unlatching winding 80, so that switch 16 opens and switch l2 shifts to its front contact. At this time the control circuit for switch ID by-passes switch l8 and goes directly to wire H. The function of the back contact of switch 18 will thus be seen to be that of providing a control circuit by way of switch III for the next machine of the series during the period of overlapping or conjoint recording on the two machines. be seen that one of the functions of the solenoid dash-pot arrangement 31-32 is to determine the length of period of overlapping recording which may be adjusted as required. A

further function of this combination is accomplished at switch 29 by completing a circuit for the start-stop winding 20 from ground through left hand contact of switch 29 and wire l9 to stop the first machine at the end of the period of overlapped recording. As an incident to this operation the lever for roller 3 now moves upwardly, breaking the circuit for relay 26 at this point. However, the circuit for this relay, has in the meantime been completed through wire so that signal light 9 indicates that a machine is in operation. The circuit for relay 24 is also broken at this time at the left hand contact with the pair controlled by the lever for roller 3, which is desirable because the carriage of the recording machine moves very slowly and would not move enough in the time represented by the period of overlapped recording to cause disengagement between contacts 22 and 23.

In one practical form of machine of this type the radial spacing between the successive convolutions of the spiral recording is about five one-thousandths of an inch, so that this auxiliary arrangement i provided to stop the first machine after a sufficient amount of overlapped recording has been accomplished.

At this point it may be noted that the attendant or the" dictator may at any time during recording on the first machine, shift to the second machine by the s mple expedient of momentarily actuating the switch of the second machine. or the desired machine of the group. Thus, if recording is going on on the first machine and the attendant or dictator see that there is some trouble with the mechanism, he may press the switch 34 of some other machine, as for example the switch 34' of the second machine, to complete an obvious circuit to the relay l3 to set the machine up for control by switch "I or switch 34; It will be noted that switch 34' also complete a circuit to the start-stop winding 20'. so that it will serve to start the second machine promptly and prepare the control circuit through switch .III for subsequent stopping and starting. The attendant may then service the first machine. stopping it in any suitable manner, as for example by momentarily closing switch 34 of that machine. Switch 60 i merely provided as a convenient means for the attendant to unlatch relay I3 at any time by completing a circuit to 31, so that the plunger apparatus.

the unlatching winding 8. The unlatching of relay l3 will not be accomplished by the closing of switch 34. i

It will not be necessary to explain how recording is transferred to the third machine from the second near the end of the recording on the second machine, since this is accomplished in exactly the same way as the shift was accomplished from the first to the second machines. It is to be noted that the cycle may be repeated if in the meantime machine I is prepared for recording, since the third machine will automatically shift recording to the first machine near the end of the recording on the third machine. This is accomplished through switch 3!" in an obvious manner, back to relay winding I3 when the contact fingers 22" and 23" engage.

A description of the operation during reproduction will now be given. Thi operation is characterized by the fact that there is no overlap of reproduction in shifting from one machine to the other because of the fact that undesired distortion would be introduced in the sound reproduction were double reproduction allowed to occur simultaneously. It is assumed that the machines are conditioned so that they are ready to start reproduction from the beginning of each record and that, of course, the record blank on the machines contain recordings. In order to reproduce, the next most important operation is to shift switch 4 from its lowermost position 'or its neutral position, depending upon which it is in at the time, to its uppermost position so that, as

is obvious, the input contact of the pair for the amplifier is connected to the reproducer 6, the output contact of the pair is connected to wire It, and the lowermost movable contact is connected to wire 28. Reproduction can then be started by momentarily closing switch ID to operate switch 13' and set the machine in motion as before. Reproduction continues until spring finger 22 engages spring finger 23, in which case the relay 24 is energized and the switches forming' part thereof are all operated as described before. The only different result in this case is that the latch releasing relay 8!! is immediately energized through wire 28 and switch 21 so that at the very instant that the second machine starts up the connection to the loud speaker 8 through switch I6 is broken so that reproduction from the first machine is instantaneously stopped. Since the records have overlapped recordings there is no discontinuity in the sound reproduction notwithstanding any physical variation in the relationship of the parts and the record tablets that might be inherent in such Of course, the second machine has started at the time the circuit I6 i interrupted, in the manner in which the second machine is started during recording, and therefore these operatlon will not be retraced. Under reproducing conditions, as in recording, the solenoid 31 will be energized so that the first machine will stop when the plunger of the solenoid closes switch 29' in the manner previously described. Thus during reproduction the circuit 46 from the first machine to the loud speaker is interrupted at the same instant that it is established through switch l6 and circuit 46'.

From the above description it will be apparent to those skilled in the art that the subject matter of this invention may be embodied-in other physical combinations and elements comprising the same, and I do not, therefore, desire to be strictly limited to the disclosure given herein in it an'illustrative apoaeoa I Y I *2. ine, system or the type described, themaensebut rather to the ecopeaoi' the claims granted me.

What is claimed is:

bination comprising a plurality of machines '10:

. recording sounds on a record and reproducing f sounds therefrom, control means interconnecting,

saidmachines and respectively controlled by said machines for causing during recording a machine in operation to start another machinenear the end of the record of the former to overlap recording for a time interval and for interrupting reproduction of one machine near the-end I 01' its record and simultaneously initiating it from another machine.

" chine. he; been initiated.

hinationcomprising a i'rlurality of machines for J "recording sounds on a record and reproducing 1. In a system oi the type described, the comsounds thereirom, control means interconnecting said machines and respectively controlled by said machines for causing during recording a machine in operation tostart another machine before the endgot recording by the former and for inter g rupting reproduction of one machine near the end of its record and simultaneously initiating itvirom another machine,'and means tor'stopping thepreceding machine a predetermined period of time after reproduction from the next ma HENRY P; cnausmr. 

